Boucher said the United States opposes provisions requiring that all members of the United Nations finance the cost of the reforms, including an international oversight body charged with inspecting detention facilities.

The United States is proposing that the costs be shared exclusively among countries that become parties to the accord.

Some human rights groups contend that the U.S. actions will dilute the effectiveness of the revised system.

Under present rules, countries are supposed to enforce the convention on their own, but rights groups say monitoring is needed because torture is still prevalent.

The protocol, which has been under negotiation for a decade, would be an optional supplement to the 1989 treaty. Its objective is "to establish a system of regular visits undertaken by independent and national bodies to places where people are deprived of their liberty, in order to prevent torture."

Boucher rejected any suggestion that the U.S. position implies a a more tolerant attitude toward torture.

"We abhor the despicable practice of torture," he said. "The United States has been one of the most forceful voices against torture."